By default, Windows servers do not accept incoming connections to SMB shares using an alias (CNAME) instead of the true DNS hostname. Such connections can result in the client receiving the System error 52 has occurred. A duplicate name exists on the network. error.

To allow servers to accept incoming connections using aliases

Use a registry editing tool to navigate to the following key:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Servic es\LanmanServer\Parameters